it can take 24 to 72 hours for changes to reach the far corners of the internet
greatbigchoices.com. is behaving like it is mapped to greatbigchoices.wordpress.com - did you also buy the domain mapping upgrade - maybe in the last few hours? Domain helper does not show mapping so I am a bit confused
If you just changed the name servers you need to let the changes work across the internet
No Domain Mapping Found
There is no domain mapping upgrade for greatbigchoices.com. If you would like to use this domain you will first need to set up domain mapping.
I will flag this for the staff to help - they have some tools I don't have and can also review your account - there are a couple of things I see that I don't understand